A digital subscriber line access multiplexer (DSLAM) is a device that allows a telecommunications company (telco) to deliver Internet access to its telephony subscribers. Typically, a DSLAM is located at the telco's central office (CO) and includes a modem subsystem that connects to a number of local loops forming part of the plain old telephony service (POTS) infrastructure leading to individual residential and business subscribers. The DSLAM also includes a routing subsystem connected to a data network (such as the Internet), thereby allowing the telco to act as an Internet Service Provider (ISP) for its telephony subscribers.
As high data rate Internet services such as video-on-demand become of increasing interest to subscribers, the issue of capacity arises. Specifically, as a consequence of requiring a much larger bandwidth than regular Internet browsing, the local loops between the DSLAM and the subscribers must be shortened. To this end, many telcos have resorted to placing their DSLAMs in an outside plant environment (i.e., outside the central office) and backhauling a high-speed communications link to the central office.
However, the placement of DSLAMs in the outside plant results in a large heat dissipation requirement brought on by the need to run both a modem subsystem and a routing subsystem in an environment where limited, if any, cooling facilities are available. This leads to an increased failure rate of outside plant equipment containing DSLAMs. It is therefore apparent that an improved DSLAM with lower outside plant heat dissipation would be a welcome improvement.